"There's a lot of history and love in the past," Morgan tells TVGuide.com in the video interview below. "Coming back to New Orleans and trying to kick him off the throne, [Klaus] has mixed feelings about the whole thing. That's what allows them to have this heart-to-heart with undercurrents of, 'I kind of want to kill you.'"

Both Morgan and executive producer Julie Plec compare Klaus and Marcel's relationship to the one on Diaries between Klaus and Stefan (Paul Wesley). "It wasn't deliberate, but in a beautiful way you understand with the history between Klaus and Marcel, why Klaus connected so quickly to Stefan," Plec says. "It's also retroactively making "The End of the Affair" episode make so much more sense."

Watch below for more from Morgan on how Klaus and the Original family are adapting to living under one roof and whether or not we'll see a return of "sensitive Klaus."

The Originals premieres on Thursday, Oct. 3 at 9/8c on The CW and then moves to its regular slot on Tuesdays at 8/7c.

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